Electromagnetic relay



Aug. 21, 1928. 1,681,473

J. ERICKSON ELECTROMAGNETI C RELAY Original Filed Sept. '7. 1920 Inuanlmr Jnhn ncxsrm Patented Aug. 21, 1928.

u "r a n ST A r terns JOHN EEICKSON, OF CHICAGO, ILLINOIS, ASSIGNOR, ."BY MESNE ASSIGNMENTS, TO

AUTOMATIC ELECTRIC INC., OF CHICAGO, ILLINOIS, A. CORPORATION OF DELA- WARE.

ELECTROMAGNETIC RELAY.

Application filed September 7, 1920, Serial No. 408,673. Renewed .Fune 20, 1927,.

My invention relates in general. to electromagnetic relays, and has for its object the provision of a new and improved slow acting relay which is slow to retract its armature when its energizing circuit is broken.

More specifically, I provide a relay which may be energized by a short impulse of current and which will then retain its armature attracted for as much as live or ten seconds, depending on its adjustment, after the energizing impulse has ceased.

There has been a frequent demand for a relay of this kind to produce a relatively long time interval in the control of electrical circuits, and it has been the practice heretofore to employ a chain of ordinary slow acting relays for this purpose. Since an ordinary slow acting relay will retain its armature only about one second at the most, quite a number of relays are required and the re-. sulting mechanism is both complicated and expensive. It will be evident therefore that a single relay which will accomplish the same object will have considerable utility.

My improved relay in its preferred form is illustrated in the drawing which will now be referred to for a more detailed explanation of the construction and operation.

In the drawing I have shown a circuit arrangement including a push button P, a slow acting relay A constructed according to the principles of my invention, and an ordinary quick acting relay B. If the push button P is actuated momentarily, the slow acting relay A will respond and will hold the circuit of relay B closed for as long as ten seconds, or thereabouts, depending on the adjustment. The manner in which this resultis accomplished will be readily understood from a consideration of the construction of relay A. This relay has a heavy slu of copper 2 around one end of the core an an armature 3 for closing contact springs 4. and 5. This much constitutes a slow acting relay of the ordinary type. I have added, however, a bracket 6 which is attached securely to armature 3 and which carries the contact springs 7 and 8. The latter spring is very flexible and has the rod 9 secured to it by soldering or other approved means. The weight 10 carried on rod 9 is adjustable up and down. When the device is at rest contact springs 7 and 8 are separated, no matter whether armature 3 is attracted orretracted. These springs are adjusted rather close together, however. v

Assume now that the push button P be momentarily depressed, thereby transmitting a short impulse of current through the winding of relay A. Armature 3 is at once attracted and closes contact springs 4: and 5, thereby completing a circuit for relay B, which also energizes. When armature 3 is attracted the Weight 10 is thrown suddenly to the right and is thus started vibrating rapidly. The vibrations will continue for a considerable interval, perhaps five or ten seconds, as previously mentioned, and during such interval the flexible spring 8 intermittently makes contact with spring 7, thereby transmitting a series of impulses through the winding of relay A. These impulses continue long after the original energizing circuit of relay A is broken at the push button, and since relay A is slow acting its armature 3 is held down as long as the weight continues to vibrate. the circuit through springs 7 and 8 is a kind of locking circuit which is automatically broken by the permanent separation of springs 7 and 8 when the weight has ceased to vibrate. When the vibration stops the relay A will receive no further current impulses, armature 3 will be retracted after an instant, and springs 4 and 5 will separate to break the circuit of relay B.

The frequency of the vibrations can be adiusted by moving weight 10 u The duration of series of vibrations, or the interval during which relay A will remain operated, can be adjusted by adjusting the stroke of armature 3 which controls the initial amplitude of the vibrations.

It will be understood that the circuit arrangement shown herein is purely for illustrative purposes and the use of the new slow acting relay is not necessarily confined to such precise circuit arrangement. A relay of this type may be interposed in any circuit in which its use is desirable and it will perform its function as set forth.

What I claim as my invention is:

1. The combination, with a relay and an energizing circuit therefor, of means inde It will be seen that or down.

pendent of the relay for closing said circuit 3 ing a locking circuit and a vibrating pendulum for controlling said locking circuit.

2. In combination, a slow acting relay, means for energizing said relay, a locking circuit for said relay, and means set in motion by said relay when the same is energized and operating independent of said relay for transmitting a; series of impulses over said locking circuit.

3. In combination, a slow acting relay and a circuit therefor, means for transmitting a momentary current impulse over said circuit to energize said relay, a locking circuit for said relay, and a mechanical device operated by the initial energization of said relay for transmitting a pre-determined series of current impulses over said locking circuit.

4. In combination, a slow acting relay and a circuit therefor, means fontransmitting a momentary current impulse over said circuit to energize said relay, a vibrating member set in motion when'said relay is energized and operating thereafter independent of magnetic attraction, and a locking circuit for said relay closed by said member while the same is vibrating.

5. In combination, a slow acting relay and a circuit therefor, means for transmitting a momentary impulse of current over said circuit to energize said relay, a vibrating member set in motion when said relay is energized and operative during a predetermlned interval of time, a l0Cl1IlgQlTCl1ltfOr said relay, and means controlled by said vibrating member for transmitting impulses over said circuit.

6. In combination, a. slow acting relay, a

circuit for momentarily energizing said relay, a locking circuit for said relay, a vibrat-' ing pendulum for transmittinga series of impulses over said locking circuit, and means for automatically setting said pendulum in motion whenever said relay is energized.

7. In combination, a slow acting relay and a circuit therefor, means for transmitting a momentary current impulse over said circuit to energize said relay, a vibratory member set in motion when said relay is ener-' gized, said vibratory member vibrating with constantly decreasing amplitude,

and a lockvibratory member, a circuit for said magnet, for

a second circuit for said magnet, means momentarily closing said first circuit to cause the attraction of said armature to initiate a. vibratory action of said member, said vibratory member thereafter vibrating with decreasing amplitude, and a contact operated by said member while vibrating for controlling said second circuit.

10. In a slow acting relay, an armature, a vibrating device set in motion by said armature when the same is attracted, a locking circuit for said relay, and a pair of contacts closed by said armature when the same is attracted and opened by said vibrating device at regular intervals thereafter to control said locking circuit.

11. In a slow acting relay, an operating circuit therefor, an armature, a vibrating device set in motion by said armature when the operating circuit is closed, a pair of contacts jointly controlled by said armature and vibrating device, and a second circuit for said relay independent of the first circuit controlled by said contacts.

12. The combination, with a relay, of a locking circuit for said relay, a non-magnetic vibrating device controlling sa1d locking circuit, and means connecting said device with the armature of the relay so that sa1d devlce is set in motion when the armature is attracted. I

Signed by me at Chicago, Cook County,

Illinois, this lst dayof September, 1920. 7 JOHN ERICKSON. 

